摘要 |
A desired programmable complex analog bandpass filter is replaced by a "black box" that receives an analog continuous-time signal and delivers an analog continuous-time signal, just as the analog filter would, but internally realizes the programmability with a programmable discrete-time system. The transfer function of the "black box" is the same as the transfer function of the analog filter. The "black box" includes an anti-aliasing filter, an A/D-converter, a complex digital bandpass filter (16), a D/A-converter (18) and an anti-imaging filter (20). |